Telephone switch apparatus.



UNITED STA PATENT OFFICE.

s'ransuw A. X OLTONIRI, OI BOITON, MASSACHUSETTS. A hSTGNOB TO ELECTED 1manual: WORKS. OI INTO], IASIACHUBETT8.A CORPORATION OF MAINE.

'rnarnon UWITOH arrana'rus.

cacao.

v lssstssattsa it Letters Patent. Application lied August ls. "a.,lertal In. 4 48.188.

lntcntcd Jun. 2-1. mm.

7b all whom it may 'eoncem:

lie it known that'I, Srasmnaw A. Konroneur, a subject of the Czar ofRussia, and

Switch A paratns, of which the following is a s i tion.

This invention relates to telephone switch apparatus for use in what iscommonly known as a private branch exchange and is for certain imrovements u :rparstue of the general aracter of t at ascribed in LettersPatent of the United States No. 846 479 issued to me March 12, 1907.

due of the objects of mg invention is to provide means whereby e trunk'line or cflitrlailelsxciis circutt will bedautgmatisa y c irrespectivean in epen ently of the operation of the switching devices controllingproperating the branch or intercommunicating circuits, thus overcoming theobjection common to i ments 0! this t heretofore used, that unletheattendan at the central inatrn t I of the branch exchange holds thetrunk ine circuit closed by manually depressing the plunfirr of thetrunk line circuit and olding it t epressed while connecting or callingone of he branch hnea, the operation of the-branch line switchingmechanism releaeesthe trunk lme switching mechanism and breaks the trunkline circuit.

Another object of my invention is to provide a separable twoart framefor the switch ap ratus. one 0 which parts carries the switc ing devicesand the means for holdin them in operative position, and the other 0which part carries the circuit contacts and circuit connections. thecoliperatmg parts upon t'hc two scct ions bcing so arranged as to comeinto their proper relationahi when the two sections arc placed togct er.

further objcct of my invention is to aggrc te all of the contacts andcircuit conncct one for cat-h branch station circuit in scpaihte groupscach upon a sin le yoke or bracket which mav be attachct to or detarhcdfrom tho ramc as a separate and complete unit.

further object 'of my invcnt-ion is to provide the rows or banks ofcircuit springs tit-contacts with lugs projecting outwardly 'thcrefromat. either side of the instrument so that. they arc readily ncccssiblcfor the at tachmcnt or dctachnu-nt of the bus bars.

Other features ot novchy and im rovcment will be hcrcinat'ter dcscri andpointed out in the claims.

.In the accompanying drawings which illustrate certain embodnncnts of myinvcntion,Figure 1 is a front elevation of an apparatns embodying theinvcntion with the cover removed; Fig. 2Vis a cros section on line 2-2of Fig. I viewed from below; Fig. 8 is a side elevation. partly insection, on finch-4i of Fig. 1; Fig. 4 is a plan view of thelatchqblates for controlling the switch ieratmg devices; Fig. 5 is aside elevation o the latch-plates showing two of the plunrs in normalposition; Fig. 8 is an enrged perspective view of one of the unit groupsof ring contact switches showing also amodi form of line connectiondevices; Fig. 7 is a side elevation of one of said unit groups showingsaid modified form of line conncction completed; Fi 8 is a detailshowing in side view a sin a latchlate which may be used in place 0 aplural I of latch-plates by cmploving a longer catch projection on thetrunlr hne lunger than those on the plangcrs for the ranch orintercomn'mnicating circuits; and Fig. 9 rcp resents diagrammaticallythe wiring or circuit conuwtions bctwccn three stations providcd with myimproved switching instrunwutsJ which is a sufiicient number for the pnrose of illustration.

en in use the instrument as a whole is placed in a vcrtical position asshown in Fig. Lwith the mciver-hmk levcr at the top, and one suchinstrument or 'apparatus is cplrovided at cacb station of the branch eaange The apparatus consists of a, base 1 upon which thc instrumcnt ismounted. A cover or box 2 incloscs and protects the instrument. Theinstrument proper oontaincd therein consists of a base plste 3 to whicha series of groups of circuit springs or contucts' is sccured in a rowalong each cdgc. One or more of these groups are to bc cmploycd fortrunk lines or main cxchangc circuits and thc others for the branch orintcrcommuuicating circuits. As illustrated in the drawinus. two of saidgroups 4" ntc employcd for trunk linc circuits and thc othcrs 4' for thebranch circuits. 'lhcrcls also employed an additional unit or group ltiU.4 which includes contacts and connections for what ma be termed anon-interfering circuit by it rich all other stations are excluded fromthe at sling or home station or from euttmF into a circuit connectedwith a trunk me. The base plate 8 is secured to cross bars 5 by which itis fastened to the base 1.

Readily separable from the base plate 8 and the parts carried thereb isa frame which consists of an inner p ate 6 and an outer plate 7connected by 8. Two

rows of plungera of which 9 9, are employed to operate the trunk linecircuits, an

lates 14, 15 and 16. he ends of the middle tch-plate 15 are ided in was18 in the posts 8. The ates 14 an 16 are suprted as herein'aterdescribed. The plate 4 serves as a latch for holding the trunk lineplungers 0 in their depressed pocition, and the plate 16 as a latch iohold the branch line luugers 10 m their depressed position to'c one thetalking circuits. For this nrpoee in or projections are pro? vided uponsai plates adapted to cooperate with catches on said plungcrs as will behereinafter more particularl dcacriimd. To rovidc free action thereoftiic plates 14 an 10 are hun at thcir cnda upon a pair of links 17, eucilink pivoted at one en to the latch plate and at the other end to theframe of the machine. Between the plates 14 and 16 lies the plate whichis operated by the de reseion of any plunger to cut out armopen t e homeCll'tltll of the calling sta- Escli plunger or switching device inprovided with a member consisting of a rail 20 ofnon-oonducting materialmounted on a stud 19. The outer ends of the rolls 20 upon the branchline plungcrs 10, are of 'smaller diameter than the inner ends for thepurpose hereinafter described. When the two sectlona of the frame. thatcontaining the plunfers and latch-plates, and that oon tainiu tic iroopsof contact springs, are placer t1 her in their proper ition, the ama erportions of the rol 20 pass between the upper ends of the a ringcontacts of the tal ing circuit, an .the larger portions of the rollscuter between the aprmgcontactsot the li ie circuits, but in thisposition, which is their normal position none of the circuits controlledby said cameo spring contacts are cloned. The closing of acid switchesin accompliahcd by the depresaion oi oaid plungera as hereinafterduscribcd.

The Imrt of the frame comprising the inner p utc 6 and outer late 7 andconnecting posts 8 carrying the plungcrs, latchplateo, receiver-hooklever and their amociatcd partn. is constructed so as to be readilyattached to or dctachrd from the plate 3 which carries the contactunite; andto facilitate and insure the accurate alincment of the twoparts 01 the frame so as to bring the coectmg mcmiiers into their roperrelation two or more dowel pins 1 are employed secured to cross bars 5,which pins paaa through pro )crly located holes in plate 0. Should it atdesired to remove the plate 7 for any put-pace, this may he emomphshcdby removing the screws at the tops off the posts 8 which hold said late,in which case the plungers may be heiii in their position by the innerplate ti, by depres in' each and passing a pin or stop through t toperforation l m the lower end of each plunger. When a trunk line plunger0 in tlepwneud its roll 20 will s read the airing contact members I" andcausing; them to moire contact respectivciy with I: and 1') thannineing; the trunk line circuit. To hold the plunger 9 deresocd it isprovided on its ower side wit a beveled tooth 22 which enga s aprojection 22" on latch plate 14. In or or to call one of theintcreummunicntin stations and to conncct.it with the trunfi line, theattendant then depresses one of the plnngcrs 10 appropriate to thedesired station. The deprcsaion of the plunger 10 causes thc roli 20 atits nmallcr diameter to spread the npriruzs c' and c causing them tomake contact respectively with the talking circuit springs c' and 0,while they are in their operative position. By depressing the plunger 10to its full extcnt, the roll 20 at Ill-l larger diamctcl' will bear uponthe inwardly projecting wings in of the contact aprin c and c apt-codingaaid upringa outward y againnt springs c and a respectively, thuecloning the 'nignnling circuit of no atation being called. lly relievingpressure on plunger 10, plunger 10 mturns-mlllicicntly to again opcn theniggnaliug circuit and close the talking circuit. the catch or tooth 22which engages latch-pinto ltl holding the talking circuit ultmul. 'l'hclll'nln'lt .ol' intcrcommunicating circuit thuu cluacd will remuinclueed until unotlu-r plunger I0 is dcprcuncd, whereupon thc tooth :29of such. plunger will more lltt' lntcll-plniu Hi and unntch theprcviously tlcprcs cd plunger 10 allowinc it to return to normalposition undcl' the inilucucc of spring ll.- lhc trunk lino plun or willremain in dc )rcsswd position unti another trunk line p on cr isdepreeccd no as to move the latch-p ate it to at one end with a post 28'secured releu-e it. or until the telephone receiver hook releul-eituhereinafter set forth.

' tin the aide of eaeh plunger ahank oppoaite to the tooth '12! is ubevel rum surlacc .4 whit-h bear:- agniust a projection on plate I! whenthe plunger is depletes-d moving the plate I.- upward and thereby movingit )wnrd a small iuaulnting roll secured to p ate it: by atud :25. Thisroll pro'ects between contact :1 rings and n of t ie group 4". The upwimnuwemeut of the roll breaks the contact between the circuit springs aand a and bet ween u and tr and thus opens the home eireuit aml preventsall other stattons from etttting into that station. This so-ealled homeeireuit is kept open by said cum surfaee ao long an any one of theplungrra is held in depremed poaitlon and 2H rhaa-d again only when allof the pluugers are returned to normal ition.

From the f ring it will be seen that the latch-plate holding the trunkline lunger or )lungers 9 is independent of an not atl'eet by theoperation of any of the other switching devices but will hold the trunkline rloaed notwithstanding the de- Emit)" of the plungera controllingthe ranch circuits.

Springs 28 under tension are connected to each "of the outerlatch-plates, and at the other end to the 28 second to the middlelatch-plate t'i aml extending through alota in the two outerlatch-plates. These Springs normally tend to urge the platenrespectively toward their operative position.

In order to restore all of the switching devices to normal positionafter a call, I provide means whereby the depresaton of thereceiver-limit lever by hanging the receiver thereon releases all the pungera both of the trunk line and of the branch lines which are then indepreiated ptatition. This restores all of the circuits to normalcondition. This means eonaitits of a dog 90 pivoted at 97 upon thelatch-plate In and told in operative position a spring 28 (see Fig. Onearm of lit ll dog is provuled with a notch against which n lateralextension 80 of a supplemental lever 81 hears. The supplemeuta lever tilis pivoted to the bracket it at 32 and carries a atnd 83 pmjeetingbeneath the receiverhook lever II. The stud 33 carries thereon a roll 34against whit-h the river-hook lever ll bears and also carries a bearingroll of insulating material, it! which aervea aa a bearing to act uponthe contacts of group 4' to open nml close the telephone eirentt whenthe receiver is lnmg up or taken down. Thedog 20 in aim provided with acurved arm it which extends over an adjustable eeeentrie atop 37 seenrmlto bracket ll in such position that when the dog 26 is depreaeed by theaction of the supplemental lever 31. which is moved by the downwardswing of the tele ihone receiver-limit lever ll. t to arm 86 wi l hebrought into contact with the eccentric stop 37 and will cause the dog26 to tilt" upon "'4 \ivot 21' until the lateral projection of i tolever :H is disengagts from the notch 29 allowing the dog and thealiding latch-platen controlled thereby to return to normal position.the pmjection 80 panning beta-ecu tlie arms 26 a 80 of the dog. liyturning the eccentric 87 upon its supporting arm the time when the dogmay be released from engagement with the pro'action 80 can be varied andregulated. 'hen the plate to la depreleledby the operation of the dog anabove deteribed. it releases the plungera controlling thetutu-communicating circuits. The ptn 88 then will engage the plate 14deprenung the same thereby releaaing the trunk hangers; thus all of theplunger-a held by t e latch-plates become released. The late 15 which isheld in elevated positton y the cam surfaces 24, will be simultaneouslyreleased with the release of the plunger-s and all the circuits will berestored olnntzmag copditiotln- I h ea 0 em 0 m 'arate ate plate forholding tile trim line plungers m their depressed position. the trunkline and the branch line plungera may be all held by a single plate andat the aame tune provision made so that the operation of the branchplungera will not release the trunk line plungera. Thiais accomplishedby the construction shown in Fig. 7 wherein the catch tooth 22' of thetrunk line plunger 9 as made longer than the tooth 92 of the branchpluuger10.tn which case after plunger 9 has been d ao that Ill tooth 2?in MM by latch late 16. the depresaron of any 0 the pangera 10 for thebranch circuita willmt release the tooth 22" because of its ter length.The latch plate may he mat a to operate properly by regulating thestrength of the moring 98 andythe springa 11 which respectively areurging the latch-plate and the nlungera to their normal poaitmna.

In Fig. 0 there is illustrated a grou or unit of contact apringaassembled and Id as a single unit complete in itself in a yoke orbracket 80 which may be readily attached to or detached from the. plate8 for the purof repair or reneu'a by acrewa through toles withoutdisturbing other parts of the ap uiratua'with the exception ofunsoldering the bun bar eonncctiona preaentiy to be described. In orderto prevent accidental contact between any two of the springs of theseveral groups. stepped atopa .41 made of insulating material may beinsorted between the springs and for the purpoae of aeenrutely loentingtrlt'h bracket 30 with refer-nee to the edge oi plate 1!, proans I waif:3 12x521.

"I, t h I s o t e a aratus.

jectiona 49 are formed upon tbbottom of each bracket to engage the edgeof plate 8. The contact prings are Iproperly insulated from each otheras usna Proiocting outwardly from each spring of tho talltin and ringingcircuits is a lug to which the us-bar is secured. These lugs arc arran lin series. ()ne series of In 44 upon t corresponding contacts of he 1several groups are preferably arranged in the same vertical plane.Another series of lugs 4a are upon their corresponding contacts of theseveral groups and are arranged in snother. plane. Another series oflugs on still other corresponding contacts are in another plane, and afourth series of in a s7 arearranged nlpon still other correspondingcontacts In a ourth plane. The bus bars 50 may then be soldered orotherwise secured to the several series of lugs and run in a strai inline without interfering one with anot er. In order that all the lugsand bus bar connections may be readily accessible for inspection andrepair by simply removing the cover from the apparatus, it will beobserved that all of said lugs project outwardly from the springcontacts at either side of the ap sratua. Heretofore it has been theraet cc to arrange bus bars in various ot ier locations more or lesscovered and obscured by portions of the apparatus so that they have beenaccessible for repair 0 by removing or dismantling certain e termin 51(see Fig. 2) are provided for the several contacts. In Fi 6 and 8 I haveshown a modified form 0 line terminal wherein an extension 52 from thecontact springs projects outward from the base in front. of the contactsand terminates 'in a U-sba piece 53. A metal stri 54 secured wit iinsaid U-shaped piece asy a screw as is fastened to the inaulatin stri 56upon the base 1, to the lower end 0 whici strips I54 the line wires areconnected. By loosening the screws as when any one of the unit groups4', 4" etc. is removed, this U- ahapet p ece as will'be removed with it.This construction afl'ords a form of line connection which need not bedisconnected from the terminals-should it be nscenary to springs fromthe housing or box.

The wiring :.of the private branch telephone svstem having threestations provided with t w improved switch apparatus is showndingrammuticnllv in big. 9. he three branch stations. hosul. 2 and 3,are counts-ted by two bell circuit wires 80 and til. and six tclcphonccircuit wires 62 to 07 inclusive. ncctcd with one of the poles of thetelephone buttery Tl by wires 72,-78 and 74, rcs wctivcly. each of saidwires including the usual impedance coil (5, while wires,68, 65 and (36remove the entire mechanism and circuit' and 69. respectively, with theoppos The wires 62. 64 and 07 are conpole of battery 71 iy wires 76, 77and 78. re-

spectively each of the la t mentioned wires including also an impedancecoil 79. The wires 60 and 61 are connected by wires 168 its es of a bellbattery 70. At each station a l of the contacts 0, of etc. are connectedby a single conductor or wire 80 with the wire 60 leading to one pole ofhell battery 70, while the wire it! that leads to the opposite pole ofbattery is connected with one terminal of a hell it at each station hv awire 81. The other terminal of each bell It is connected by a wire 82with the contact e of its station. The contact c at each station withwhich a is normally in engagement. is connected by a wire 83 with thecontact a of the home switch of its station, and each wire 83 isconnected by wires 84 with the contacts'c, d.

etc. of its station and by a wire 85 with the contact I) of the trunkswitch of its station. At station No. l the contact a with which contacta is normally in engagement, is connected by a wire 86 with wire 05; at.station No. 2 the contact a is connected by a wire 87 with wire 67; andat station No. 3 said contact a is connected by a wire 88 with wire 68.It will now be seen that the bell circuit for each station includes wire81, bell B, wire 82. contacts e and a. wire 83, contacts a and a. andwires 86, 87' and 88. At stations Nos. 2 and 3 the switch d, d etc. isthe branch switch for calling and controlling communication with stationNo. 1. and the contacts 4!" of both of these branch switches areconnected each by a wire 89 with thewire 64 to which the wire 105connects contact a of station No. 1. At stations Ros. 1 and 9 thecontacts c. 0' etc. is the branch switch for Eli calling and controllingcommunication with station No. 3, and the contacts c' of these two.

No. 2. The contacts 0. and I! of these twowitches are connected each bya wire ill ith the wire (ill. with which the wire 106 of station No. 2connects. Assuming now that the operator at station o. 2 or No. :ldesires to ring the bell of station No. 1. then be pushes. in. to thelinnt of its movement. the

usb button 10 of branch switch (I, (1' etc. of iis station. and as longas he holds this push button in its extreme iuncr )osition n circu'it iscom )lctc through he] ll of station No. l. whici is traced as follows:from buttery 70 through wires 0H and (it wire 81 of cameo cs I'tl-t' mayby: contacts I! and 1; and thence lhrou 'h \tn cs H). lit) and il backto battery 7". t will now be plain how the operator sure from such pushbutton the bell B at the called station ceases to ring. At each stationthe contact a of the home switch is connected by a wire 93 withone ofthe terminals of a transmitter T, the other terminal of which isconnected through a wire 94 with the contact 0', said wire 04 includingthe primary of an induction coil I. The contact a with which contact 4:cooperates is connected by a wire 95 with the wire on. The secondary ofthe coil 1 is connected by wires 90 and 97 with the receiver R. Thecontact b of the trunk switch is connected by a wire 98 with the wire93, while the two middle contacts 6' and b are connected with the trunkline wires tit! and 100 leading to central.

It will now be clear that when the trout: switch button of any stationis pushed in and the receiver it removed from its book, a trunk lineleading to central is closed, which is traced at the branch station asfollows: from wire 99 through contacts 6 and b; wires 85, amt U5contubts of and wire 94 including the primary of induction coil 1;transmitter '1; wires 93 and 98; and contacts b and b to wire 100. Sincethe latch-plate 14 for the trunk awitch is entirely indcpendent of thebranch switch buttons 10, any one or more of the latter may hedepreiaaal after the trunk switch button has been de usual, and thosebranch cwitch buttons wil be caught and held in their inner 't ons bythe latch plate 18; but if the ranch switch buttons have been depre-edpreviously to the operation of the trunk awitch button, then when thetrunk switch button ia depreaaed the cam 941 of the latter will operatethe late 10 so as to return these branch awitci buttons, auto maticall'to normal ition, leaving only the trun line ctinn with the station.

At each branch station the wire 08 is connected wirea 101 with thecontacts or, d etc. of t e respective branch awitchca of the station. Atstation No. 1 the contact d which coogeratea with the-contact d of thatswitch an at station No. 8 contact a are each connected by a wire 108with wire 67. At atationa Noa. 1 and 2 the contacts 0 which cooperatewith contacta c' of those switches are connected by a wire 102 with thewire 68. At atationa Nos. 2 and 3 the contacts at which cooperate withthe contact ll of those switches are connected by wires 104 with thewire iii At station No. 1 the wire 64 is connected by a wire 105 withthe contact a" of the home switch of said at.- tion; at utution No. 2the contact a" of the home switch of that station is connected by a wire106 with the wire titi. and at hluiiutt .\'o. 3 the contact a of thehome switch of that. station is connected by a wire 10? with the wire03, its explained above the contacts u and u of the home switch of eachbranch station are normally closed as are also the contacts a? and a ofsaid switch. Also it has heretofore been made clear that the change inthe condition of the circuits and switches at the called station isreducod only by the removalof the receiver R from its book in respondingto the call which opens switch 0, c, and closes switch e, 0. Therefore,if station Xo. 1 is the called station its pin-i of the primary talkingcircuit is from wire ti! through wire 86; contacts a, 0'; wires StrandU7; contacts c",

a; wire 94; transmitter '1; wire 93; contacts a, a, and wire 10? to wire64. That part of the primary talkin circuit at the calling station isostahlishet by pushing'in the button 10 eorres mnding tothccalledstution, which operation serves to establish said trircuit from eitherwire U2, (it or tilt, according to which push button 10 is operatedthrough the transmitter of the calling eta tion to wire 63, (5.: or (ii.'lhus if station No. 2 in calling :iiutimt No. 1 push button at switchZ,Z is depressed and caught by plate It), so that that part of theprimary talkin circuit at station No. 2 is from wire tit) witt whichwire 86 of station No. 1 connects, through wire 104; contacts d and d ofthat switch; wire 93; (contacts a and 'a' of the home switch being oicncd at the calling station tht'ottrrjh the tcprteeiion of the pushbutton in caiiing station No. 1) transmitter '1; contacts c,-i:'-',-wires 95 and 83 (contacts a and a of the home switch being opened at theccllin station through the depression of the past button in calling attion No. 1), contacts (1 and d of that awitch and wire 89 to wire 64with which wire 105 of station No. l connects.

ii claim: 7 t

1. .tdelcplmnc switch apparatus for con trolling a p uralit of circuits,of which one or more is a trun line or central exchange circuit, and theothers are branch or inter= connnunicatiug circuits, comprising aseparate switching device for each circuit tn the system, aml movableretaining means adapted automatically to hold the trunk line or centralexchange circuit cloae'd independently of the operation of the switchingdevices controlling the branch circuits.

2. A 'tele hone switch apparatus for controlling a p uralit of circuits,of which one or more is a trun line or central exchange circuit, and theothers are branch or intercouununicating circuits, comprising asc'puratc switching device for each circuit in the system, means wherebythe o ration of any of the switching devices con rolling the hng thebranch circuits.

3. A telephone switch apparatus-for co trolling a p uralit of circuits,of which one or more is n trun line or central exchange circuit, and theothers are branch or intercommunicnting circuits, com risin a series ofswitching plungers, one or one circuit, a spring for each plungernormally urging the same toward its elevated or inopsrative' position,and movable retaining means adapted automatically to engage and holddepressed the Inn r or plunger-s controlling the trunk ine circuitirrespective of the operation or the switching plung r-a o! the branchcircuits.

4. A tele hone switch apparatus for controlling a p urolit of circuits,of which one or more is a trun line or.central exchange circuit, and theothers are branch or intercommunicatin circuits, com irisin a series ofswitching p ungers, one or eac circuit, a spring for each plungernormally urging the same toward its elcvatcd or inoperative position,means whereby the depression of an) of the branch circuit plun era willrelease other branch circuit p nngcrs previously depressed, and movableretainin means adapted automatically to engage on hold depressed theplunger or plungers controllin the trunk line circuit orcircuitsirrespective of the operation of the pluugcro Offilhi lzrincg:circuitrtl. h f

. so one swi c a arutus or controlling aapi uralit. pp or niore is atrun line or central exchange circuit, and the others are branch orintercomnninicating circuits, com n'ising a separate switching devicefor each circuit in the system. and menus to hold the trunk line orcentral exchange circuit closed, irrespective of the operation of liswitchcscontrolliug the branch circuits, n lazt'ttt' .or sup rting thereceiver, and lllt'ttlh controlled snid lever for ratil nll oi theclosed Swilclus to restore all of t to circuits to normal conll. Atelephone witch apparatus for controlhng a p uralit of circuits, ofwhich one or more is a trun line or central exchange circuit, and theothers are branch or intcrcommunicutin circuits, com wish] a scrics ofswitching plnizfera, one or can circuit, and means to 01 depressed theplunger or of circuits, of which one.

Mam

plungem controlling the trunk line switch or switches irres tive of theo aeration of the switching iungers of the ranch circuits, a lever orseiiipporting the receiver, and means controll y sai lever for releasingall of the depressed switching plunger-s to restore all of the circuitsto normal condition.

7. A tele hone switch apparatus for controlling a p uralit of circuits,of which one or more is a trun line or central exchange circuit, and theothers are branch or intercommumcatin circuits, com risin a series ofswitchin p ungers, one or eac circuit,

,antomatical y operated means to hold depressed the plun rs of thebranch circuits, and an automatically operated latch to engage and holddepressed the trunk line plunger or lungers, irres tire of the o erationof t e means em 0 ed to hold elungers of the ranch circuits. 8. A telepone switch apparatus for controlling a. p uralit of circuits, ofwhit-tibiae or more 18 a trun circuit, and the others are branch orinterconnnuuicsting circuits, comprising in series of switchingplungers. one for each circuit. n latch-plntc adapted to engage and hohldcprcnm'tl the plungrrs of the hrnnch circuit. and an imlc ndcntlatchlate uduplctl to engage and mid dcprcsscti the trunk lino plungeror plungcrs irrespective of thc operation of the first lncntioncdlntclrplutc.

9. A tclc )hone switch apparatus for conirolling a piurulitr ofcii'tftllls'. of which mic or more is n trun linc or control cxchungocircuit. and the others are branch or iutcrcommunicating ('ilflLits,comprising u scrics of switching plungcrs, one for cnch circuit. nlatch-pinto uduptcd to cngngo nlnl hohl depressed the plnngcrs of thebranch circuits and on imlcpcmlcnt lntch-plutc mlnpt- ('(l to engage andhold tlcprcmul llit' lrunk line plunger or pluugers' irrcspm-tiro' ofthc opcration of the first nicntioucd lutrlhplnlc. and u thirdlntchilutc controIIc lhy the operation of any p uugcr of the series. themovement of whici plutc opcus a circuit to exclude all othcr'circuitsfrom the one conncctcd with the home station.

it). tclcphonc switch uppurntns for controlling n plurnlitv of circuits.of which one or tllm'ois u trun linc or control exchange circuit. andthe others are ln'nnch exchange or intcrmnnuunicnting circuits,coniprisin n .wl'it's oi su-itchingtpluugcrs. one for t'llti circnitrulutcli inln itcil to cugngc uml liultl ilcpicescil tho plungcrs oft'nlu'onch cir' cults. nn-uns \rhcrcl r tlic lit';-l'thltlll of any oucof Hllltl ln'nuch circuit p ungcr-a l'tlt'liht'.\ anytilltttlwlt'plt'xsml brunch circuit pining-or. ttii liitltpt'mlcttllulcli :ulu itml t0 cugjnglulnl hold depress-ml thc li'lllH Iinc plnngcror )lllll crs irrcspcctivc ot tlnlrt'lltlit ll ol'thc run s circuitliilllljfll'w'. :iml u iilil'ti latch line or central exchange ano 1,

t'ttlllltlllt'tl by the opera ion of any plunger in the r 'lltri. thelnot'elttt'llt of whi h open it circuit to exclude all other circuitsfrom the home station.

ll. telephone min-h up mrutm for coutrolling u pluralit of circuits,which one or more, it an Iron line or central exchange circuit..- andthe others ure brunch exchange or iutcrmmnntnicating: circuih. comm-hing11 series of switching plunger one for each circuit, a latch adapted toengage and hold deprwml the nlnngera ot the brunch eirt'tllltt. menus \rn-reby the dc men ion of any one of mid branch circuitpiuntzera releuawany other tl 'pl't'm'tl brunch circuit plump-r:

un iudo iendeut lutch tltlll llt'tl to engu and l Il hold depresiedthc'trun lino plunger or plun cro irrespective of the operation of thell'flllt'll circuit plungere. and a third latch controlled by theoperation oftanv plunger in the neriee. the movement of n'hic 1' opcnn acircuit to exclude all ,otllcr'circnite from the home ntation. and meansto operate all of said latches together to release all of acid plun rsand restores" of said switches to nonna condition.

12. A telephone witch apparatus for controlling a pluralitv of circuits.of which one operation of any plunger of the series, the

movement of rich opens. a circuit to exelude all other circuits from thehome 'statron, a lever for aupportln the telephone receiver, and meanscontro ed by said lever for operating all of said latch-plates torelease all of said plunge", and restore all of said awitches to normalcondition.

18. In a telephone switch apparatus rovided with a aerieh of switchingdeviceav teld in operative position by one or more latchpl tea, thecombination with the telephone receiver-book lever, of a supp ementallever pivoted to the ap ratua and operated [a he receiver-hook ever, aring controll 7 dog pivotedto one of the etch-plates, and means upon thesupplemental lever to enga the dog and move I together yntl the latelates to release all of the switching devices meld by laid latch-platen,when the receiverhook lever is dew-eased 14.In a telep one switchapparatus pro- ..M d with a plurality of circuits and 0. comes'zceiver-hoo said latch-plates. means operated by the reof au'itchingdevices therefor held in operutivo poxitiou by u plurality of print;actuated ltlltill-llllllththe combination with the telephonercccivcr-hmxl: lever, of a nupplemental lever pirated to thett|l]ltll'tll-llli and operated by the mritel'dnmlt lover. a wiring"controlled dog pivoted to one of the etchplates, Incnlln upon theflnpplonu-ntal lever to engs tl dog and move it together with the latei-plute to which it is pivoted to open the circuits controlled thereby,means on auclrlatch-plato simultaneously to o hereto theother latchlateato restore the c reuitn controlled there y to their uortnalfixaiitionand means to release said dog from can aupilemental lever to. permit allof the lat r-plates to retgrn to their normal posihon after said mtcheshav'e'been restored to normal position.

- 15. Ina teleph switch apparatus for ,controlh a' p urn ity of circuitsand pr'ovided wit a seriea of switching devices which are lield inoperative position by one 7 or more spring actuated latch-plates, urelever, a dog pivoted to one of eetver-hook lever to entrain anddepress the do and its latch-plate, and a fixed stop adapted to engageand actuate the pivoted dog to release it from the operation of thereceiver-hook lever to permit said latchplates to return to normalition.

10. In a tele hone nwitc apparatus for controllin a p urality ofctrcultirand provided wit a series of switching devices which are heldin operative .pmition by one or more a ring actuated lutch-phitea, areceiver-h lever, a dog pitoted to one of aaid-latch-platen, meansoperated by. the receiver-hook lever to engage and depm the dog and itnmotuniuul a stop adapted to engage and actuate to pivoted dog to releaseit from the operation of the receiverhool: lever, said stop comprisingan adjuateble eccentric whereby t release ma be varied.

17. A telephone awitch apparatus for controlling a plurality ofcircuits. comprising u readily separable two-purt frame. one of whichparts curries the uu'itching devices.

springs normally holding the same in in-.

operative position. and menus to hold them in operative position and toreleaae thcm therefrom, am the other of which parts car rica groups ofcooperating circuit spring. toget \er with bus bars connecting the some.and means to guide the two parts of the frame when placed together so asto bring the switching devicesinto proper cuiipcrutire relationship orulineun-ut with thenrerun-tire circuit nprinun. the ill'Hl nu-ntiom-dpart being no comtrueted that the relative potutionu of the dericmcurried thereby are not diaturbed when the two parts of the frame areseparated.

to time of such llli IN. A telephone switch ll] l|ttll'lllllt4 forcontrolling a plurality of ircuits, comprising a readily separable twopart frame, one of,

I said plungers. and the other of whiei iarts lib - contrnlling ii pconsists of a base plate having secured t iereon a bank of maps ofcircuit springs and means separab y to fasten said two parts togetherwith the members carried thereby in cooperative relationship.

19. A telephone switch apparatus for controlling a plurality of circuitscomprising a readily separable two part rame. one of which frame-partscarries the switching dcvices. the springs normally holding the uwitchinllitl springs retained between and abutting against said switchingdevices and said frame-part. and the means to hold said switchingdevices in operative ition and to release them therefrom. it frame-partand said devices carried in-why being wholly self contained whereby saiddeviceswill not be disnnanbered or disturbed when the two parts of theframe are separated, and the other of which frame-parts carries groupsof cooperating circuit contacts together with bus bars connecting thesame. said two parts and said devices i'especlit'el i' carriedtherebymaeh being complete in itself and so constructed that each partand the devices carried thereby are not di ineinlwreil or di turbed whenthe two parts are separated.

20. lml'|tlttllltfJaWiit'll apparatus for controllitig a plurality ofcircuits. comprising a readily separable two-pait frame. one of whichparts consistsof an inner plate and an outer plate provided with guidesfor the switching pliiugers, said plates connected together by posts,plnngers in said guides carr \'ingcontact springo icrating members, andlongitudinally moral) e latch-plates holding depresstal said phingei's,and the other of which parts consists of a base plate having scent-edthereon a bank or group of circuit contacts. and means to guide the twoparts of the frame when placed together so as to bring theswitchingdevices into eol'qieratii'e relationship with their respectivecircuit contacts.

2t. in a trio ihone s\"ilch apparatus for liii'alitv of circuits ainlprovided with a series of switching plnngci's. a frame comprising anouter guide plate for said phingeis and ttdmltlllttl inner plate hariiigapertures to gni c the inner ends of said plnngers, the inner ends ofsaid plnngers (lei-ices in inoperative position,- I gage with outcharacter described comprisin adapted to pass through said apertur s,each iiiingeiprov ded with a slion der and held l a spring with theshoulder abutting against said outer guide plate, said outer with meansto receive and hold a separable stop to prevent. the plungcrs from beingforced out of tlicirinner guiding apertures when the outer guide plateis removed.

22. In a telephone switch apparatus for controlling a p uriility ofcircuits, in combination, a base having thereon a series of gron s of awin contacts, each group assenib ed an bed in a se ai'ate bracketadapted to be readily attac ed to and detached from said base as'asingle unit, and a separable frame carrying a pluralit of switchingdevices coo crating each with i appropriate group 0' circuit contacts,said brackets lnivin projections ada )tcd to onbase to insure tieaccurate positioning of said contacts in relation to said 'switchindevices.

23. In a tee hone switch apparatus for controlling a p urality ofcircuits, in combination, two parallel. rows of groups of spring circuitcontacts, pli ngcrs to operate said circuit eontacts,'the talking andringing swings of said circuit contacts being provided with lugs, thelugs on the springs of each row being on the outer side of the row andprojecting away from the other row, whereby bus-bars connected to saidlugs will be situated entirely outside of the rows of iipl'iltgti.

24. In it tele ihone switch apparatus for controlling a p nrality ofcircuits, in combination. two parallel rows of groups of spring circuitcontacts, plun rs to 0 rate said circuit contacts, the talking andringing sprin gs of said circuit contacts being provide with lugs, thelugs on the s wings of each row being on the outer side 0 the row andprojecting away from the other row, and the series of lugs on thecorresponding contacts of each group being in alincment itiid in thesame plane, and each of such series of tags being in irditfcrcnt planefrom any other series, whereby the bus-bars when connected to theirrespective series of lugs will be'sitnated entirely outside of the rowsof springs and in separate tiers.

2 ..A telephone switch apparatus of the in combination a frame, ailurality of circuit springs and switching plnngcrs, and a springactuated plate for holding the plungg'ers cicprezised, said plate beingsupported to swing in a email are in the. frame by links ivotc at oneend to the frame and at the at an end to the plate whereby slidingfriction is avoided.

lit)

met). A telephone switch a character descrilx'd comprising incombination, a frame, a plurality of circuit springs and switchingplungcrs one or more of which controls the trunk line, and the rest ofwhich pparatus of the I able plate vieldiu l v hcl control the branchlines. a spring actuated latch-plate for holding the trunk 'liuc plaugeror pluugcrs depressed, and a spring actuated latch-plate for holding thebranch line plungers depressed, each of said platcs ing hung at its endsby links pivoted to said frame and to said plate.

27. In a tele hone switch apparatus of the character eacribcd, thecombination with tho ilungcr and latch-plate carrying a frame. 0 alaterally extending arm secured. to said frame at the end thereof. comarising the plate I! having the upturned end it 'proridcd with a mentallever 31 pivoted to acid plate c use to said upturned end ll, and atelephone receiver-hook lever pivoted to Hold late ll oppoai e to thepivot of lever M an extending through said alottcd end B','nieansintermediate the supplemental lever and latch plates to release thelatter. and means intermediate the sup lt'mcntal lever and thereceiver-hook lever w icrebv the depression of the latter operate thearmor.

28. la a telephone switch apparatua of the character dem-rila'd. a groupof circuit a iringa consisting of a pair of inner springs or the talkingcircuit. a pair of ontcra irings for the signaling circuit, and a pair 0intermediate apriiiga for the line circuit. all of said apriuga beingnormally electrically di ponuccted from one another. and each of Midline circuit apriugs ha ring an extension or wing ofl'oet from thelinc.of the other 8 rings, in combination with a switching; p un .rcarrying a stud extending laterally there roni, one portion of thc .-tudadapted to enter bctwccii the talking and force thciu outwardly agniu-tthc liuc circuit springs during the tirat part oi the downward movementof the plunger. and another portion of said stud adapted to enterbetween the extensions or wings on the line circuit. 8 rings and forcethem out of con- ;tacthwiti the talking circuit npriugs and into contactwith the aigualingz circuit springs durinf a further downward movementof the p anger.

20. A telephone switch apparatus for controlling a plurality ofcircuits. comprising in combination a series of switching plungers meansto engage and hold depressed suitiplanners, a

lephone circuit. controlled by slut thcrcthroinzh, a i-aipilecircuitprings itudiniilly movin inoperative eani-eigiagin cechof .-aidplunpera. a loii pu-itiou am provit cd with a surface. each of saidpluiigcra provid wit a coin to shift sillti plate lengthwise, and meanswhereby the movement of said plate by the cam of any one of stlitlplungera opens a circuit to c\'clude from the home'atation all thetelephone circuits controlled by the other ilungers.

n a telephone switch apparatus of the character de cribed, a group ofcircuit '-'s rii iga consisting of a pair of inner springs for thetalking circuit, a pair of outer springs for the signaling circuit. anda pair of intermediate sprin for the line circuit, all of mid apriuiiabeing normally electricall v diaconucctcd from one another. and each ofsaid line eircuitsprin having an extension or wing otl'i-et from theline of the other springs, in combination with a switching plungercarrviug a stud consisting of two portions of ditl'erent diametersextending aterally therefrom, the rtion of the stud of the. smallerdiameter a opted to enter between the talking circuit aprin and forcethem outwardly ap'ainst the ine c'irciiit apriuga during the iii-at partof the downward movement of the plunger, .and the other portion of saidat'ud of the larger diameter adapted to enter between the extensions orwings on the line circuit sprin and ftll't't' them out of contact withthe talking circuit springs and into contact. with the signaling circuitaprin during a further downward movement o the plunger.

31. A telephone switch apparatus for controlling a plurality ofcircuits. comprising in combination a series of switching plungers meansto engage and hold depressed saii plungcra, a telephone circuitcontrolled h each of said plungers, a movable plate icl iugly held ininoperative position an vided with cam-engaging surfaces, said pluug'craprovided with came to enga aitid cam-engaging surfaces and move nan lateand menus wherebv the movement 0 min plate by the cam of' any one ofsaid lungem opens a circuit to exclude from he homo ntution all thetelephone circuits controlled by the other planners.

Signed by me at llloeton. Massachusetts, this 5th day of August, 1908.

Ciuauca D. Womanizer, Romain Clioiiamii.

